drivers/ata/libata-zpodd.c

   1 #include <linux/libata.h>
   2 #include <linux/cdrom.h>
   3 #include <linux/pm_runtime.h>
   4 #include <linux/module.h>
   5 #include <linux/pm_qos.h>
   6 #include <scsi/scsi_device.h>
   7
   8 #include "libata.h"
   9
  10 static int zpodd_poweroff_delay = 30; /* 30 seconds for power off delay */
  11 module_param(zpodd_poweroff_delay, int, 0644);
  12 MODULE_PARM_DESC(zpodd_poweroff_delay, "Poweroff delay for ZPODD in seconds");
  13
  14 enum odd_mech_type {
  15         ODD_MECH_TYPE_SLOT,
  16         ODD_MECH_TYPE_DRAWER,
  17         ODD_MECH_TYPE_UNSUPPORTED,
  18 };
  19
  20 struct zpodd {
  21         enum odd_mech_type      mech_type; /* init during probe, RO afterwards */
  22         struct ata_device       *dev;
  23
  24         /* The following fields are synchronized by PM core. */
  25         bool                    from_notify; /* resumed as a result of
  26                                               * acpi wake notification */
  27         bool                    zp_ready; /* ZP ready state */
  28         unsigned long           last_ready; /* last ZP ready timestamp */
  29         bool                    zp_sampled; /* ZP ready state sampled */
  30         bool                    powered_off; /* ODD is powered off
  31                                               * during suspend */
  32 };
  33
  34 static int eject_tray(struct ata_device *dev)
  35 {
  36         struct ata_taskfile tf;
  37         const char cdb[] = {  GPCMD_START_STOP_UNIT,
  38                 0, 0, 0,
  39                 0x02,     /* LoEj */
  40                 0, 0, 0, 0, 0, 0, 0,
  41         };
  42
  43         ata_tf_init(dev, &tf);
  44         tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
  45         tf.command = ATA_CMD_PACKET;
  46         tf.protocol = ATAPI_PROT_NODATA;
  47
  48         return ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
  49 }
  50
  51 /* Per the spec, only slot type and drawer type ODD can be supported */
  52 static enum odd_mech_type zpodd_get_mech_type(struct ata_device *dev)
  53 {
  54         char buf[16];
  55         unsigned int ret;
  56         struct rm_feature_desc *desc = (void *)(buf + 8);
  57         struct ata_taskfile tf;
  58         char cdb[] = {  GPCMD_GET_CONFIGURATION,
  59                         2,      /* only 1 feature descriptor requested */
  60                         0, 3,   /* 3, removable medium feature */
  61                         0, 0, 0,/* reserved */
  62                         0, sizeof(buf),
  63                         0, 0, 0,
  64         };
  65
  66         ata_tf_init(dev, &tf);
  67         tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
  68         tf.command = ATA_CMD_PACKET;
  69         tf.protocol = ATAPI_PROT_PIO;
  70         tf.lbam = sizeof(buf);
  71
  72         ret = ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
  73                                 buf, sizeof(buf), 0);
  74         if (ret)
  75                 return ODD_MECH_TYPE_UNSUPPORTED;
  76
  77         if (be16_to_cpu(desc->feature_code) != 3)
  78                 return ODD_MECH_TYPE_UNSUPPORTED;
  79
  80         if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1)
  81                 return ODD_MECH_TYPE_SLOT;
  82         else if (desc->mech_type == 1 && desc->load == 0 && desc->eject == 1)
  83                 return ODD_MECH_TYPE_DRAWER;
  84         else
  85                 return ODD_MECH_TYPE_UNSUPPORTED;
  86 }
  87
  88 static bool odd_can_poweroff(struct ata_device *ata_dev)
  89 {
  90         acpi_handle handle;
  91         acpi_status status;
  92         struct acpi_device *acpi_dev;
  93
  94         handle = ata_dev_acpi_handle(ata_dev);
  95         if (!handle)
  96                 return false;
  97
  98         status = acpi_bus_get_device(handle, &acpi_dev);
  99         if (ACPI_FAILURE(status))
 100                 return false;
 101
 102         return acpi_device_can_poweroff(acpi_dev);
 103 }
 104
 105 /* Test if ODD is zero power ready by sense code */
 106 static bool zpready(struct ata_device *dev)
 107 {
 108         u8 sense_key, *sense_buf;
 109         unsigned int ret, asc, ascq, add_len;
 110         struct zpodd *zpodd = dev->zpodd;
 111
 112         ret = atapi_eh_tur(dev, &sense_key);
 113
 114         if (!ret || sense_key != NOT_READY)
 115                 return false;
 116
 117         sense_buf = dev->link->ap->sector_buf;
 118         ret = atapi_eh_request_sense(dev, sense_buf, sense_key);
 119         if (ret)
 120                 return false;
 121
 122         /* sense valid */
 123         if ((sense_buf[0] & 0x7f) != 0x70)
 124                 return false;
 125
 126         add_len = sense_buf[7];
 127         /* has asc and ascq */
 128         if (add_len < 6)
 129                 return false;
 130
 131         asc = sense_buf[12];
 132         ascq = sense_buf[13];
 133
 134         if (zpodd->mech_type == ODD_MECH_TYPE_SLOT)
 135                 /* no media inside */
 136                 return asc == 0x3a;
 137         else
 138                 /* no media inside and door closed */
 139                 return asc == 0x3a && ascq == 0x01;
 140 }
 141
 142 /*
 143  * Update the zpodd->zp_ready field. This field will only be set
 144  * if the ODD has stayed in ZP ready state for zpodd_poweroff_delay
 145  * time, and will be used to decide if power off is allowed. If it
 146  * is set, it will be cleared during resume from powered off state.
 147  */
 148 void zpodd_on_suspend(struct ata_device *dev)
 149 {
 150         struct zpodd *zpodd = dev->zpodd;
 151         unsigned long expires;
 152
 153         if (!zpready(dev)) {
 154                 zpodd->zp_sampled = false;
 155                 zpodd->zp_ready = false;
 156                 return;
 157         }
 158
 159         if (!zpodd->zp_sampled) {
 160                 zpodd->zp_sampled = true;
 161                 zpodd->last_ready = jiffies;
 162                 return;
 163         }
 164
 165         expires = zpodd->last_ready +
 166                   msecs_to_jiffies(zpodd_poweroff_delay * 1000);
 167         if (time_before(jiffies, expires))
 168                 return;
 169
 170         zpodd->zp_ready = true;
 171 }
 172
 173 bool zpodd_zpready(struct ata_device *dev)
 174 {
 175         struct zpodd *zpodd = dev->zpodd;
 176         return zpodd->zp_ready;
 177 }
 178
 179 /*
 180  * Enable runtime wake capability through ACPI and set the powered_off flag,
 181  * this flag will be used during resume to decide what operations are needed
 182  * to take.
 183  *
 184  * Also, media poll needs to be silenced, so that it doesn't bring the ODD
 185  * back to full power state every few seconds.
 186  */
 187 void zpodd_enable_run_wake(struct ata_device *dev)
 188 {
 189         struct zpodd *zpodd = dev->zpodd;
 190
 191         sdev_disable_disk_events(dev->sdev);
 192
 193         zpodd->powered_off = true;
 194         device_set_run_wake(&dev->tdev, true);
 195         acpi_pm_device_run_wake(&dev->tdev, true);
 196 }
 197
 198 /* Disable runtime wake capability if it is enabled */
 199 void zpodd_disable_run_wake(struct ata_device *dev)
 200 {
 201         struct zpodd *zpodd = dev->zpodd;
 202
 203         if (zpodd->powered_off) {
 204                 acpi_pm_device_run_wake(&dev->tdev, false);
 205                 device_set_run_wake(&dev->tdev, false);
 206         }
 207 }
 208
 209 /*
 210  * Post power on processing after the ODD has been recovered. If the
 211  * ODD wasn't powered off during suspend, it doesn't do anything.
 212  *
 213  * For drawer type ODD, if it is powered on due to user pressed the
 214  * eject button, the tray needs to be ejected. This can only be done
 215  * after the ODD has been recovered, i.e. link is initialized and
 216  * device is able to process NON_DATA PIO command, as eject needs to
 217  * send command for the ODD to process.
 218  *
 219  * The from_notify flag set in wake notification handler function
 220  * zpodd_wake_dev represents if power on is due to user's action.
 221  *
 222  * For both types of ODD, several fields need to be reset.
 223  */
 224 void zpodd_post_poweron(struct ata_device *dev)
 225 {
 226         struct zpodd *zpodd = dev->zpodd;
 227
 228         if (!zpodd->powered_off)
 229                 return;
 230
 231         zpodd->powered_off = false;
 232
 233         if (zpodd->from_notify) {
 234                 zpodd->from_notify = false;
 235                 if (zpodd->mech_type == ODD_MECH_TYPE_DRAWER)
 236                         eject_tray(dev);
 237         }
 238
 239         zpodd->zp_sampled = false;
 240         zpodd->zp_ready = false;
 241
 242         sdev_enable_disk_events(dev->sdev);
 243 }
 244
 245 static void zpodd_wake_dev(acpi_handle handle, u32 event, void *context)
 246 {
 247         struct ata_device *ata_dev = context;
 248         struct zpodd *zpodd = ata_dev->zpodd;
 249         struct device *dev = &ata_dev->sdev->sdev_gendev;
 250
 251         if (event == ACPI_NOTIFY_DEVICE_WAKE && pm_runtime_suspended(dev)) {
 252                 zpodd->from_notify = true;
 253                 pm_runtime_resume(dev);
 254         }
 255 }
 256
 257 static void ata_acpi_add_pm_notifier(struct ata_device *dev)
 258 {
 259         acpi_handle handle = ata_dev_acpi_handle(dev);
 260         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
 261                                     zpodd_wake_dev, dev);
 262 }
 263
 264 static void ata_acpi_remove_pm_notifier(struct ata_device *dev)
 265 {
 266         acpi_handle handle = ata_dev_acpi_handle(dev);
 267         acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY, zpodd_wake_dev);
 268 }
 269
 270 void zpodd_init(struct ata_device *dev)
 271 {
 272         enum odd_mech_type mech_type;
 273         struct zpodd *zpodd;
 274
 275         if (dev->zpodd)
 276                 return;
 277
 278         if (!odd_can_poweroff(dev))
 279                 return;
 280
 281         mech_type = zpodd_get_mech_type(dev);
 282         if (mech_type == ODD_MECH_TYPE_UNSUPPORTED)
 283                 return;
 284
 285         zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL);
 286         if (!zpodd)
 287                 return;
 288
 289         zpodd->mech_type = mech_type;
 290
 291         ata_acpi_add_pm_notifier(dev);
 292         zpodd->dev = dev;
 293         dev->zpodd = zpodd;
 294         dev_pm_qos_expose_flags(&dev->tdev, 0);
 295 }
 296
 297 void zpodd_exit(struct ata_device *dev)
 298 {
 299         ata_acpi_remove_pm_notifier(dev);
 300         kfree(dev->zpodd);
 301         dev->zpodd = NULL;
 302 }